The proposed Gordon Conference is the third dealing with the molecular mechanisms of microbial adhesion to surfaces. Structures of microorganisms which may be involved in adhesion are surface lectins, surface proteins bearing extended hydrophobic domains, lipoteichoic acids, teichoic acids, peptidoglycan, teichuronic acids, capsular mole- cules, lipopolysaccharides, pili or fimbriae, fibrillae and flagella. Much of the conference will be devoted to attachment of bacteria to host tissues, prior to colonization, activation of the receptor-bearing cell 2nd appearance of symptoms A question to be addressed in the conference is what governs specificity. Why should some organisms have a high affinity for mucosal surfaces, and others mainly for hydrophobic surfaces? What are the evolutionary advantages of adhesion to specific surfaces? Are cell cycle events related to adhesions? Answers to these questions will increase our knowledge of the process of infection by human pathogens. The other major issue relates to environmental factors determining gene expression. Several sessions will be devoted to detailed discussions of these topics with the understanding that adherence to surfaces is regulated in part by the bacteria, but also by the surface or host cell. The overall plan for the conference is to procure scientists with outstanding expertise on all facets of microbial adhesions so that a truly challenging and interdisciplinary meeting can be held. Foreign scientists have made significant contributions to these studies. Funds are requested for travel for some of these scientists, as well as for remission of conference fees for all non-USA invited participants. In addition, funds are requested for junior US scientists to partially defray travel and to provide conference fees. Based on interest in the field, it is anticipated that this will be an important Gordon Conference, for basic scientists as well as workers in the applied fields of dental research, infectious disease and environmental health.